Taper-thread-cutting machine.



L. B. CURTIS & C. E. JOSSELYN.

TAPER THREAD CUTTING MACHINE.

APPLICATION FILED DE(1.17.1913.

1,11 5,055, I Patented 001;. 27, 1914.

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Patented Oct. 27, 1914.1

TAPBR THREAD CUTTING MACHINE.

APPLIOAllON FILED B30417, 1913.

L. B. CURTIS 82; G. E. JOSSELYN.

gl-rwe'wfow UNITED STATES PATENT OFFICE.

LEWIS B. CURTIS AND CHESTER JOSSELYN, 0F BRIDGEPORT, CONNECTICUT, ASSIGN- ORS TO THE CURTIS & CURTIS 00., OF BRIDGEPOR-T, CONNECTICUT, A. CORPORATION OF CONNECTICUT.

Specification of Letters Patent.

TAIPER-THREAD-CUTTING MACHINE.

Patented Oct. 2'7, 1914.

Application filed December 17, 1913. Serial No. 807,204.

Cutting Machines; and we do declare the following to be afull, clear, and exact description of the invention, such as Wlll enable others skilled in the art to which it appertains to make and use the same This invention relates to the sub1ect of screw tlnead cutting, and has particularly in view a machine for cutting taperlng threads.

' ing out the objects of the invention as generally stated above, it will be understood that the same is susceptible to changes in details and structural arrangements, one simple and practical embodiment thereof being shown in the accompanying drawmgs, wherein Figure 1 is an end view of the improved taper thread cutter. Fig. 2 is a side elevation, partly in section the section being taken on the line 22, Fig. 1. Fig. 3 1s a fragmentary perspective view of a portion of the guide sleeve showing one ofthe cutter guides therein. Fig. 1 a detail perspective view of a cutter or die adapted for use in connection with this invention. v

The improved; taper thread cutting machine comprises in its general organization a stationary frame or holder 1 having an internal annular flange 2 at one end through which the bolts crfteud for clamping the pipe or other article 4 that is to be threaded.- The opposite end of the' frame may be thickened as indicated in Fig. 2 for strengthening urposes, and is provided with the internal threads 5. At a point preferably intermediate of the threads 5,

the holder 1 is provided with a flat external annular flange or ledge 6.

The internal threads 5 of the holder 1 are engaged by the external threads 7 of the die carrying sleeve 8, said sleeve 8 having end flanges 9 forming seats for dies 10, said dies being especially designed for use in connection with this machine, as will be apparent from the following description.

A guide sleeve 11 surrounds the carrying sleeve 8 in spaced relation and has an internal annular flange 12 that seats on the ledge G of the holder 1 The sleeve 11 incloses their? ledge 6 and it has a holding ring 13 bolted or otherwise detachably fastened to its base that overlaps the base of ledge 6, the arrangement being such that the said sleeve 11 can be rotatedon said ledge, but relative longi-' tudinal movements of the sleeve and ledge are prevented. Internally, and beyondthe ,flange 12, the sleeve 11 is provided with a plurality of rounded radial grooves 14 that are inclined and extend longitudinally of said sleeve, the flange 12 forming the bottom of each of said grooves. The inclined rear wall 15 of each groove forms a cam surface.

and at the front, each groove is contracted to. form the oppositely disposed ribs 16 which are inclined'i'n p'arallel relation to the cam surfaces 15 and have beveled sides 16". The cutting dies are made to conform to the shape of the grooves 14 by formin site sides ofthe junction of their b0 ies and heads 17 with inclined grooves 18 which are of a size to snugly receive the ribs l6 and ihave beveled sides 19. The sides of the heads 17 are rounded and their free ends are fiat and inclined, as indicated at 20, correspondin ly with the inclination of the cam sur- ,faces 15.

With the described shape of the grooves il l'and heads 17 of the dies 10 in mind, it .will be seen that said heads will snugly, but ,slidably fit in the said grooves; the grooves 18 of the heads interlocking with the ribs OPPO- 16 and the ends 20 of the heads slidably consleeve; but such ring permits the dies to freely slide transversely of sleeve 8.

As is clearly shown in Figs. 1 and 2 of the drawings, the dies or cutters 10 are'firmly held in the grooves 14: of sleeve 11 against transverse movements relative to said sleeve, the engagement between said dies and the ribs 16 being a snug interlocking one, yet

such dies are freely slid-able longitudinally of said grooves. The grooves 14- and ribs 16 being inclined, and the heads 17 of the dies being correspondingly shaped, it will be apparent that movements of the dies longitudinally of the gmoves produces a cam action that causes said dies to move trans versely of the sleeve 8.

As aforesaid, the sleeve 8 is threaded to holder 1; sleeve 11 is rotatably attached to flange 6 of holder 1, and the dies 10 are held to the sleeve 8 against movements longitudinally of said sleeve 8. it will therefore be clear that when sleeve 11 is rotated by means of the handles 21, or otherwise, the dies 10 will rotate sleeve 8, and said sleeve 8, through its threaded connection with holder 3, will move longitudinally of said holder and in such movements, the dies 10 will travel "with ;--leeve 55 causing them to slide longitudinally the cam grooves 14: with the result that the said dies will simultane or move transversely of the ring The grooves l-i are open at their outer ends, clearly shown in Fig. 2, and itwill. be understood that by causing the sleeve 8 to move outward, the dies will slide from said grooves, whereupon the said dies can be readily withdrawn from between the sleeve 8 and the ring or other holder 22. This arrangement obviously facilitates the removal or replacement of the dies.

it will be observed by referrirreto Fig. l, tl it the SlllVC 11 is provided with a plurality of sets of grooves or sockets 14-, the members of each set being diametrically opposite. By this arrangement a plurality of sizes of pipes or rods may be threaded with the same dies. For example, as shown the dies are set for a 2 pipe. If a 1 pipe is to be operated on, the dies would be shifted to the l sets. The drawings show the sockets arra ged for pipes or rods of sizes from 1" to 2", but of course more or less could be used.

From the foregoing description it will be seen thatthis invent-ion provided simple and eflicient means whereby the dies, through their interlocking engagement with the grooves or sockets of the sleeve 11, are firmly held againstand vibratory movements that would damage the threads, yet such dies are freely movable to the different necessary po sitions for cutting taperiig threaus.

As has been explained, the sleeve 11 has its die sockets 14 arranged in sets for various sizes of work. And it has been ere plained that a continued outward movement of thercarrier 8 will lift the dies 10 from the sockets. Such arrangement and operation of the parts facilitates shifting the dies from one set of sockets to another set, in that when the dies are lifted from said sockets they, are still held to the carrier, whereupon by rotating either the guide 11 or the carrier 8, the dies may be alined with and readily placed in the desired sockets.

What we claim as our invention is:-

l. A taper threading machine comprising a work holder, a die carrier movable longitudinally thereof, a die guide having internal longitudinally extending inclined sockets provided with oppositely disposed inclined ribs, and a die seated on and transversely movable of the carrier and provided with means for interlocking with the sockets and the ribs to prevent transverse movement c the die relative to the sockets and permit longitudinal movements of the die relatively to the sockets.

in a taper threading machine, the com longitudinally inclined and having contract-- ed 01. on sides provided. with o positcly disposed ribs, and dies having heads shaped to interlock with the sockets and provided with side grooves to interlock with the ribs.

4. A taper threading machine comprising a work holder, a die carrier movable longitudinally thereof, a plurality of dies carried by and slidable transversely of the carrier, means for preventing the dies moving lengthwise of the carrier, said dies having heads provided with inclined side grooves, and a die guide having a plurality of inclined sockets and inclined ribs with which said head and grooves interlock.

5. A taper threading machine including a die carrier, :1 guide rotatable relative to the carrier and provided. with internal. sockets that are longitudinally inclined and pr0- vided with fiat inclined rear walls and haw ing contracted open side provided with inclined ribs that are parallel to said rear wall and dieshaving heads shaped to snugly but slidabl v fit in the sockets and provided with side grooves with which the ribs interlock.

6. A taper threading machine comprising a work holder having an external annular ledge, a carrier carried by and movable lon' gitudinally of the holder, a guide surrounding the carrier in spaced relation and having an internal flange seated on one surface of said ledge, means for fastening the guide to the opposite surface of said ledge to prevent other than rotary movements of said guide, and dies seated on the carrier and guided by the guide.

7. In a taper threading machine a die carrier, a rotatable guide provided with a plurality of die guiding sockets arranged in radial relation, said sockets being arranged in sets that are arranged in graduated relation relative to the-size of the work that is to be threaded and provided with means for interlocking with dies, and dies adapted for selective engagement with the sets of said sockets and the interlocking means thereof.

8. In a taper threading machine, a die carrier having a plurality of internal radially disposed longitudinally extending cam sockets provided with ribs, and dies having heads shaped for firm interlocking engagements with the sockets and ribs to prevent the dies having movementsother than longitudinally of said sockets.

9. In a taper threading machine the combination with a work holder, a die carrier longitudinally movable thereof, a plu 'ality of radially arranged dies normally held to the carrier, and a die guide surrounding the carrier in spaced relation and rotatably connected to the holder, the carrier being adapted to be projected beyond the guide to remove dies from said guide and said guide being provided with a pluralit of sets of radially arranged die sockets a apted to be selectively placed in positions to receive the dies carried by the carrier.

In testimony whereof We afiix our signatures in presence of two witnesses.

LEWIS B. CURTIS. CHESTER E. JOSSELYN. Witnesses:

M. A. I'IOPKINS, F. W. SMITH, Jr. 

